Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (GERMANY)


The ZSW is one of the most renowned German research institutes in the fields of photovoltaics, energy systems analysis, renewable fuels, battery technology and fuel cells. About 170 scientists, engineers and technicians are currently employed at its three facilities in Stuttgart, Ulm and Widderstall. They generate a turnover of more than 20 million euro. The ZSW has a strong commitment in the photovoltaic technology area, including thin film technology (CIS), PV-systems (modules, inverters, storage), as well as special applications (building integration, façades, tracking, lighting).
ZSW has about 170 employees and is well equipped with all machinery for the small scale fabrication and analysis of CIS thin film solar modules up to a size of 30 cm x 30 cm. Based on the expertise in CIS technology a certified world record cell efficiency of 20.1% was realised in 2010 (area of 0.5 cm²). ZSW successfully transferred the CIS technology into the industrial production line at Würth Solar. The machinery at ZSW lab comprises PVD (thermal evaporation, sputtering), CVD, chemical bath deposition, substrate preparation, interconnection and encapsulation. Two different patterning systems equipped with scribing tools and lasers are available for the purposes of laser ablation, photolithography and micromachining. These patterning systems have been prototypes for the equipment now used in industrial production and are used as a platform for the development of laser processing.
The analytical equipment comprises XRD, XRF, SEM, EDX, WDX, SNMS, SIMS, XPS, UV/VIS spectroscopy, Raman spectroscopy and equipment specific for the investigation of solar cells (solar simulator, quantum efficiency, laser scanning (LBIC), Hall-effect, accelerated ageing test, sheet resistance, reflectivity, mechanical tests etc.).
ZSW co-operates with the universities of Stuttgart, Ulm, Karlsruhe and others and is a member of the German Renewable Energy Research Association (FVEE). ZSW is also involved in a number of important national and international PV circles and contractor or co-ordinator of EU research projects (e.g. LARCIS, PV-MIPS).

 

 

Role in the project

 

ZSW will provide CIS thin film modules on glass, polyimide and steel substrates for the tests of patterning by use of fiber lasers within WP4. ZSW is also involved in laser scribing in WP5 and in the diagnostic activities of WP7. For these tasks long lasting experience and a complete laboratory pilot line for the CIS module fabrication are available at ZSW.

 

 

Key personnel to be involved in the project activity includes

 

Erwin Lotter is a physicist with more than twenty years experience in thin film solar cell fabrication. Upon completion of his PhD thesis on amorphous silicon, he started working on the up-scaling of the CIS technology at ZSW, where he is responsible for the patterning of CIS modules. He has designed the patterning systems of the Würth Solar pilot line and has advanced experience in laser processing, process automation and several analytical methods. He has coordinated national and international projects.

 

Roland Würz: 1988-1994 Study of physics at Justus Liebig University, Giessen. 1995-2001 PhD student at Hahn Meitner Institute, Berlin, Department "Silicon Photovoltaics", 2001 PhD thesis at Philipps Universität Marburg "CaF2 Pufferschichten in Silizium Heterostrukturen", 2001-2004 Postdoc at Hahn Meitner Institute, Berlin, Department "Heterogeneous Materials", 2005-2006 Institut für Physikalische Elektronik, University Stuttgart, since 2006 at ZSW, project coordinator of the FlexNet project (functional layers for flexible, low cost CIS thin film solar cells). Roland Würz has a great deal of experience with CIS technology on flexible substrates, but he is also familiar with other PV techniques.